Karl Barth was certainly onto something when he kept Mozart spinning on the gramophone, um, you know, "the record player," as he himself spun out the 6 million words of the Church Dogmatics. I cannot imagine trying to concentrate at all, much less analyze deep theological problems while listening to opera, but the symphonies move right along, and when it comes down to sheer productivity, somehow I always seem to get a lot more done than I imagine possible when the symphonies of Mozart are running in the background.
At present I am having fun loading them onto iTunes in numerical order. I am no musicologist, but I do realize there are critical and historical problems with this approach. Nevertheless, I also think it gives one a general sense of how the great composer developed by listening to things in (grossly) chronological order, and in fact, I find this developmental approach to anyone's output, whether musical, theological, sermonic, etc., is almost always the most revealing.
So then, why not start with his so-called "Youth Symphonies"?